| 摘要 |
PROBLEM TO BE SOLVED: To realize a motor controller for inexpensively enhancing a resolution. SOLUTION: The motor controller comprises an edge counter 6 for counting an edge of a pulse signal from an encoder for generating the signal within a window time based on a window reference signal, a number-of-edges latched circuit 8 for holding the counted edges, latched circuits 9, 10 for holding the numbers of 1/m multiplication signal of a shorter interval of a period than the pulse signals in both regions before and after pulse counting in which the pulse signal within the window time is not detected via a 1/m multiplication signal counter 7, and a rotational speed calculating circuit 11 for calculating the rotational speed based on the number NE of the edges and the numbers Ns and Ne of the 1/m multiplication signal. Thus, its resolution can be raised without increasing the frequency of the output signal of the encoder. A signal cable and a connector for connecting the encoder and the motor controller as well as an I/O circuit do not need components dealing with the high-frequency (expensive), their noise resistance needs not to be raised and even when its performance is enhanced, its cost does not rise. |
